General information about on-board electrical equipment

When checking an electrical system, a motorist in technical documents each time encounters such concepts as voltage, current and resistance.

Voltage is measured in volts (IN), current strength - in amperes (A) and resistance is in ohms (Ω). Voltage in relation to a car is usually understood as the voltage of the battery. In this case, we are talking about a constant voltage of about 12 volts. The voltage value depends on the battery charge and ambient temperature and can range from 10 to 13 volts. On-board voltage, on the contrary, is created by the generator and at an average engine speed, this voltage is approximately 14 volts. The concept of 'current strength" in the field of automotive electrics is relatively rare. The value of the current strength is indicated, for example. fuses, and this value corresponds to the maximum current in the electrical circuit at which the fuse does not blow and the circuit is not de-energized.

Flowing through an electrical circuit, current must overcome resistance. The resistance depends, among other things, on factors such as the cross-section and material of the conductor, the value of the current drawn, etc. If the resistance is too high, the electrical system will malfunction. For example, the resistance of high voltage wires should not be too high, otherwise it is impossible to obtain an electric spark of sufficient strength, which ignites the fuel-air mixture and thereby creates the prerequisites for the operation of the car engine.